The invention provides a high voltage lithium ion secondary battery cathode material, which is represented by a general formula LiNi0.5-xMn1.5-yMx+yFzO4-z. Specifically, M is one or several elements of Mg, Cr, Ti, Co, Al, Fe, Zn and Cu, x is greater than or equal to 0 and smaller than or equal to 0.1, y is greater than or equal to 0 and smaller than or equal to 0.2, Z is greater than or equal to 0 and smaller than or equal to 0.2. The invention also provides a preparation method of the cathode material. The method includes: firstly employing a coprecipitation technique to generate a carbonate precursor of a nickel salt, a manganese salt and an M salt, then mixing the precursor with a lithium salt and LiF, performing ball milling, and carrying out fast microwave sintering to obtain the sample LiNi0.5-xMn1.5-yMx+yFzO4-z. The preparation method has the advantages of simple and controllable production process, short heating time, and low energy consumption, thus being suitable for large-scale industrial production. In the invention, an anion-cation composite doping way is adopted, the advantages of anions and cations are utilized comprehensively, and simultaneously their disadvantages can mutually offset, and the generated synergistic effect can improve the battery performance. The material prepared by the invention has completely developed crystal grains with moderate and uniform size, and has the advantages of high voltage, high capacity, excellent rate performance and high temperature cycle performance, etc.